High WIP degrades quality, increases cycle times, and delays feedback loops. By establishing strict WIP limits on Kanban boards or development pipelines, you force the system to finish existing work before taking on new tasks. This shifts the team's mindset from "starting things" to "finishing things." Principle 3: Reduce Batch Sizes
The Principles of Product Development Flow: Second Generation Lean Product Development Donald G. Reinertsen is a foundational text for modern Agile and Lean management. High WIP degrades quality, increases cycle times, and
To achieve fluid development flow, you must establish an economic framework where every decision is translated into a single lifecycle metric: profitability. The most critical variable in this framework is the . Reinertsen is a foundational text for modern Agile
In manufacturing, excess inventory sits visibly on the factory floor as stacks of parts. In product development, inventory consists of uncompleted designs, untested code, and unvalidated requirements. This inventory is invisible, and it collects in queues. Why Queues are Dangerous They increase the time it takes to get feedback. They age the information, making it obsolete. They delay the realization of economic value. How to Control Queues In manufacturing, excess inventory sits visibly on the
Perhaps the most transformative insight in the book is the nature of queues. In manufacturing, Work-In-Process (WIP) inventory is visible—piles of parts on a factory floor. In product development, queues are invisible; they are piles of information waiting to be processed, features sitting in backlogs, designs awaiting review, or code waiting for deployment.
Cost of Delay is the financial impact of delivering a product or feature late. If launching a feature next month instead of this month costs your company $50,000 in lost revenue, your CoD is $50,000 per month. Understanding CoD allows teams to prioritize work based on monetary value rather than urgency or loudest opinions. Sequencing Work with WSJF